Injectable filler, which is often applied in minimally invasive surgery, has been widely-used in facial rejuvenation. Because of its convenience, effective usage and less downtime after treatment for the patients, it becomes one of the most popular treatment methods at present. The currently available products containing collagen base have been proven to have much satisfactory safety and effectiveness, but one of its disadvantages is the lack of long-term volume persistence. We have previously prepared the reconstituted collagen fibrils with hyaluronic acid (HA) by modifying the fibril surface. This study is to evaluate the potential of these materials as injectable filler in vitro. A preparation of collagen fibrils with a diameter of 100–150 nm was used. The modification rate of HA on the fibril surface was 20%. In assessment of the biocompatibility, it was proven that the collagen fibril and HA-collagen fibril treated with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) had no cytotoxicity or inhibitory actions. In interactions between these materials and cells, it was found that the existence of HA could improve the migration ability of L929 fibroblasts and breast cancer cells (MDA-MB 435s). In conclusion, collagen fibril and HA-collagen fibril have the potential to be developed into an injection as a soft tissue filler for biomedical applications.
